Heater



6 Sheets-Sheet l HEATER G. R. LAWRENCE Filed April 17, 1922 dnzfenl 'cr 6207 96 .Lawmu'e Bu 0 #01 2 0 July 21, 1925.

as L- July 21, 1925. 1,546,592

I G. R. LAWRENCE HEATER Filed April 17, 1922 6 Sheets-Sheet 5 20 Jnz/eni'or 1 71-6356 G'emzqe Lawrence A I A I dli'orne y.

Jul 21, 1925.

6 Sheets-Sheet 5 G. R. LAWRENCE HEATER Filed April 17, 1922 July 21, 1925.

G R. LAWRENCE HEATER Filed April 17, 1922 6 Sheets-Shea; 6

Patented July 21, 1925.

UNITED STATES GEORGE R. LAWRENCE, OF CHICAGO, ILLINOIS.

HEATER.

Application filed April 17, 1922. Serial No. 553,816.

To all whom it may concern:

Be known that I, GEORGE R. LAWRENCE, a citizen of the United States, and a resident of Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Heaters, of which the following is a specification.

This invention relates to improvements in a heating apparatus, and particularly to that type of such apparatus wherein liquid or fluid fuel is burned to provide the heating medium for residences, apartments, factories, enameling or other high temperature ovens, for the generation of steam for heating or power purposes, or in fact, for almost any domestic or industrial purpose.

One of the objects of the invention is, the provision of a structure or heating apparatus of such construction and arrangement of its parts, that it will cause practically all of the heat produced in the combustion chamber, or that part of the conduit for the passage of the products of combustion where the initial burning of fuel takes place, and in said conduit up to the flue or smoke stack of the apparatus, to beradiated or conducted from said chamber and conduit (instead of being discharged through the flue and wasted as heretofore) and confined and distributed or directed in a manner to be most efficiently utilized for whatever purpose desired.

Another object 18 to provide a heater of such characteristics or construction, that the parts thereof which are necessarily subjected to intense heat may be made of quite thin material, which is desirable in order that heat may pass through said material quickly, and also, in such a way that the area of their radiating or outer surfaces shall be greatly in excess of their inner or absorbing surfaces, to the end, that such elements will be prevented reaching or attaining a selfdestroying temperature.

The invention further contemplates the utilization of currents of heat absorbing media surrounding the conduit for the passage of the products of combustion and directed counter or in an opposite direction to the draft through said conduit for the purpose of quickly conducting the heat from the conduit.

Still another object of the invention is to provide a heater which shall be port.-

able, that is, made up of detachable units, to the end, that one or more units can be employed, depending on the amount of heat required for a given purpose.

A still further object is the production of a heater having a conduit for the passage of the products ofcombustion made up of separab e sections disposed one above the other whereby they may be easily detached for cleaning or repairing.

The above named and other objects and advantages of the invention will be more readily understood when read in conjunction with the accompanying drawings, in which several forms of the invention are illustrated, any one of which may be employed, depending upon the desires or requirements of the user.

Referring now to the drawings,

Fig. 1 is a side view party in section and partly in elevation of a. form of the heater in which air is employed as the heat absorbing and distributing or conveying medium, taken on line 11 of Fig. 2 but showing the casing with one of its sides omitted.

Fig. 2 is a front face view thereof.

F ig.' 3 is a greatly reduced fragmental sectional view taken on line 33 of Fig. 1, showing baflles' adjacent the conduits of the heater.

Fig. 4 is a greatly reduced diagrammatic view looking from the rear face of the apparatus and illustrating a modification in the construction and arrangement of the baflles.

Fig. 5 is a side view partly in section and partly in elevation of a form of the heater in which water is employed as a heat absorbing and distributing or conveying medium, taken on line 5 5 of Fig. 6, but showing one side of the casing removed.

Fig. 6 is a view partly in section and partly in elevation taken on line 66 of Fig. 5 looking in the direction indicated by the arrows.

Fig. 7 is an enlarged view of a portion of one of the sections of the conduit of the heater showing means for connecting said portion to a like portion of an adjacent section of the heater.

Fig. 8 is a side view partly in section and partly in elevation of a form of the heater, in which steam is generated and dispensed therefrom, taken on line 88 of Fig. 9.

Fig. 9 is a vertical sectional view taken on line 99 of Fig. 8 looking in the direction indicated by the arrows and Fig. 10 is an enlarged plan view of a portion of one of the sections of the conduit of the heater employed in the construction shown in Figs. 8 and 9, taken on line 1010 of Fig. 8.

Fig. 11 is a view similar to Fig. 1 and illustrating a modified form of the invention disclosed by said figure;

Fig. 12 is a view similar to Fig. 5 and illustrating a modification of the invention as disclosed thereby; and

Fig. 13 is a view similar to Fig. 8, and disclosing a modification of the invention therein disclosed.

In the drawings, I have shown one unit only of each of the forms of the heater, and in the following description and explanation, will refer to one unit only of each form, as the units of each section, when more than one is employed, are of like construction.

Referring now more particularly to Figs. 1 to 4 inclusive of the drawings, the reference numeral 15 designates a rectangular uprlght casing which is preferably made of sheet metal and has within the same, a rectangular inner casing or lining 16 which as shown in Fig. 1 is spaced from the outer casing to afford a dead air chamber, thereby reducing the heat conductivity of the easing. Communicating with the upper portion of the innercasing 16 is an air inlet pipe or conduit 17 which as shown in Fig. 1 extends from 'near the front face of the casmg to near its rear portion, thus affording a horizontally elongated passage-way for the intake of air. Near its lower end, the cas mg is equipped with a heated air outlet 18 which is disposed in a similar manner with respect to one side of the casing, as that of the air inlet above mentioned.

Mounted on the upper surface of the base 19 of the casing and within the latter, and extended from near the front face of the casing to near its rear face, is a U-shaped bracket 20 on the upper ends of the prongs of which is mounted the lowermost section of the conduit for the consumption and passage of the products of combustion, which lowermost section may be termed the fuel chamber of the heater.

As shown in Figs. 1 and 2, the conduit for the above mentioned purposes of the unit comprises the horizontally disposed fuel chamber or lowermost section 21, and aplurality of superimposed sections 22, 23, 24, 25, and a vertically disposed flue or smoke stack 26, which latter is extended throu h the top of the casing 15 and its lining. 6f course, it will be understood that the number of sections composing the conduit can be varied,

without a departure from the spirit of the invention. The section 21 or the fuel or combustion chamber of the form of the heater now under consideration, is provided with a series of annular and spaced flanges 27 which extend from one end of said section to the other end thereof. The front end of the section 21 co-incides with an opening 28 in the front portion of the casing 15 located at a suitable distance above the outlet opening 18 of said casing. Fitted in the opening 28 and the adjacent end of the section 21, is a Venturi tube 29, which as shown is horizontally disposed and is of the ordinary construction of such tubes, except that it has in its lower portion a longitudinally extended slot 30 which is for the purpose of draining excess or unconsumed oil which may collect in the bottom of the section 21 by reason of flooding said section accidentally. This tube 29 is surrounded externally of the easing with a spaced housing 31 which is used for holding between it and the tube 29 packing 32 of asbestos or other suitable non-heatconducting material.

In this construction of the heater as well as in the other two forms thereof, a draft regulator consisting of a housing 33, see Fig. 5, surrounding the outer end of the tube 29 and secured to the outer face of the housing 31, may be employed. This housing, as shown in Fig. 5, is equipped with a depending hollow member 34 which has within its lower extremity a damper 35 hinged at its upper edge to one of the walls of the member 34 and by preference to the outer wall thereof. The housing 33 has a spout or lip 36 extended from the lower portion of the front end of the tube 29 so as to cause the oil or liquid fuel which may flow through the slot 30 to drain directly and verticall through the hollow member 34 of the dra t regulator.

It will be understood that the fuel for the heater may be of liquid or fluid form and is forced into the inwardly tapered outer end of the tube 29 by means of a nozzle or fuel supplying device (not shown), which nozzle or device is connected to a source of fuel supply under pressure. The rear end of the section 21 of the heater conduit is upturned as shown in Fig. 1, and terminates in a horizontally disposed external flange 37 which co-incides with and supports a similarly disposed flange 38 on the rear end of the section 22 which is located horizontally and longitudinally above the section 21. The flanges 37 and 38 of the sections 21 and 22 respectively may be secured together by means of bolts 39 and nuts 40 engaging the same in such a manner as to prevent leakage.

As each of the superimposed sections of the conduit of the heater of the form now under consideration are ofv identically the same construction, a description of one of said upper sections will sufiice. Each of these upper or superimposed sections consists of an elongated hollow conduit provided within its cavity with a series of longitudinally and radially disposed flanges 41 which are spaced from one another and terminate at their inner edges in a circuit concentric with the longitudinal axis of the section yet at a distance therefrom.

Each of the upper sections, like the lower or combustion chamber section 21 of the conduit, is provided on its periphery with spaced annular flanges '27 which extend from one end of the section to the other end thereof as shown. The opposite ends of each section are disposed at substantially right angles and vertically to the body of the section and in opposite directions from one another. Each of these vertically extended ends is provided with a horizontally disposed annular flange 38, which flanges are tightly secured together in pairs at the front and rear portions of the heater casing, thus securely uniting the sections of the conduit together into a manifolded or serpentine form, the sections of the conduit being located in a vertical plane. In order to more securely fasten the upper sections together, one or more pair of flan es 27 of each of the sections has horizontal y mounted thereon and transversely with respect to the section, a plate 42, which plates are located diametrically opposite each other and on the upper and lower surfaces of said flanges. By this arrangement it isapparent that the plate or plates 42 carried on the lower portion of an upper section, will co-incide with the similar plate or plates carried on the upper portion of the lower section adjacent thereto and that said plates can be securely fastened together by screw-bolts and nuts or rivets.

Communicating with the upturned end of the uppermost section of the conduit is a flue or smoke stack 26 for the outlet of smoke and unconsumed particles of carbon. The front wall of the casing is provided with one or more door-ways 43, which when more than one of such ways is employed, are located one above the other as shown in Fig. 2. Each of these door-ways 43 is closed by a door 44 hinged at one of its side edges to the front of the casing. As shown in Fig. 1, the upper sections of the conduit, that is, those sections above the combustion chamber section 21, communicate at their front ends with one another in pairs and similarly at their rear ends. However, the front ends of each pair of said sections are open so as to permit of access to the interior of said sections through the front wall of the casing after the door 44 covering 'a pair of said sections has been opened. The open front ends of each pair of the said upper sections may be tightly closed when the heater is in operation, by means of a door 45 hinged at one of its side edges to one side of the doorway 43.

Vertically mounted on each side of the conduit and extending from the lower edge of the inlet opening 17 of the casing to about the'upper edge of the outlet opening 18 is a baffle 47 which as shown in Fig. 3 is provided with cross-sectionally curved portions 48, which curved portions lie one above the other and in close proximity to the flanges 27 of the various conduit sections. These crimped or cross-scctionally curved baflles 47 will cause the air as it is forced into the casing through the inlet opening 17 to pass downwardly between the baflle plates and in contact with the various sections of the conduit and their peripheral flanges, to the end that the heat radiated from the conduit will be absorbe by the currents of air and discharged through the outlet 18 in a highly heated condition.

In Fig. 4 is shown a modification in the construction and arrangement of the baflles, which consists in employing a horizontally disposed baffle plate 49 located longitudinally alongside theuppermost section 25 of the conduit and its flanges and extending from the front of the casing to the rear thereof and between one of the side walls of the casing and the said conduit section. Located longitudinally and horizontally alongside the section 21 and between said section and the side wall of the casing from which the outlet conduit 18 leads, is another baffle plate 50 which as shown, lies above the outlet 18. By this last named arrangement of the baffle plates it is manifest that as air is forced through the inlet opening 17 and thence downwardly, the baffles 49 and 50 will cause the currents of air to take such passage through the casing as to cause them to be brought in contact with the various sections of the conduit and their radiating flanges.

In Figs. 5 to 7 inclusive of the drawings is shown a modification in the construction of the heater, which modified form comprises the casing 15 equipped with an inner casing or lining 16 and with door-ways in its front wall in a similar manner to that shown in Figs. land 2 and above described. In the form of the heater now under consideration, water is employed as a heat absorbing and distributing or conveying medium. Horizontally located in the lower portion of the casing 15 and mounted on suitable supporting members 51 extended upwardly from the base of the casing, is the fuel or combustion chamber section 52 0f the conduit for the passage of the products of combustion. This conduit, like the first above described one, is made up of a series one on the other and the lowermost one thereof on the combustion chamber section 52. Each of the sections above the section 52 is provided in its longitudinal bore with a plurality of longitudinally and radially disposed flanges 41 which are spaced from one another and terminate at their inner edges in a circle concentric with the longitudinal axis of the section yet at a distance therefrom. Each of the sections including the lowermost and the uppermost one, which sections may be of any desired number, is surrounded with a water jacket 62. Each of said sections, with the exception of the lowermost section 52, is provided at its ends with oppositely extended hollow extensions 63, which extensions are located in a vertical plane and at substantially right angles to the body of the section. The lowermost section 52 has one of these extensions 63 at its rear upper portion, but the front end of said section is without said extension but has fitted therein the Venturi tube 29 and its equipment as above specified in connection with the first described form of the heater. The extension 63 of the section 52 co-incides or registers with the extension 63 on the lower rear portion of the section 53 of the conduit, and it will be understood that the front and rear ends of all of the sections of the conduit above the combustion chamber conduit 52 are alternately connected in pairs by the necks or hollow extensions 63, thus providing a circuitous passage-way for the products of combustion from the section 52 to and through the uppermost section and from thence through the flue 26 to a suitable point of discharge.

Longitudinally mounted on the lower surface of the section 52 is a tubular header or coupling 64 which has communication through an inlet or supply pipe 65 which leads from a source of water supply not shown. The header or coupling 64 communicates through openings 66 with the water jacket 62 of the section 52 and is secured to said section by means of bolts 67 each of which has on one of its ends a head 68, see Fig. 7, which head is located in a countersunk opening 69 and resting on a washer 70 between which washer and the inner surface of the section 52 is placed suitable packing 71 to prevent leakage. The outer ends of the bolts 67 extend through the tubular header 64, the outer surface of which may be provided near each of its ends with a countersunk opening similar to that shown at 69 in Fig. 7. The outer ends of these bolts may be equipped with a washer 70 and packing 71 to prevent leakage and may have secured on their outer ends nuts 72 for securely holding the tubular header in position. By this arrangement it is apparent that provision for the flow of water to the water jacket 62 of the section 52 from a source of water supply, is provided. The

upper portion of the water jacket 62 of the section 52 is provided with openings 73 to register with openings 74 in the lower portion of the water jacket 62 of the section 53 located adjacent and above the section 52. These two sections are secured together by means of bolts 67 which have their headed ends seated in countersunk and packed openings 69 in a similar manner to that just above described in connecting the tubular header 64 to the lower portion of the section 52, and as is clearly shown in Fig. 7 of the drawings. This manner or means of connecting the water jackets of the various superimposed sections of the conduits in communication with one another is carried out throughout the entire series of the sections of the conduit.

It will be understood that the registering passage-ways or opening 7 3 and 74 are provided with means surrounding them for preventing leakage of water. Mounted on the upper portion of the uppermost section of the conduit of this modified form is a tubular header or coupling 75 from which leads out through the casing a distributing or discharging pipe 76 for the water heated by the apparatus.

In Figs. 8 to 10 inclusive, is shown another modification of the heater, which form is for the generation and distribution of steam. In the present modification the conduit for the burning of fuel and the passage of the products of combustion thereof is, as in the other two constructions, formed of a lowermost or combustion chamber section 77 and a plurality of superimposed sections 78, 79, 80 and 81, although the number of said sections may be varied. As before stated, these sections are mounted one on the other in a vertical plane and communicate one with another from the lowermost one to and including the top one, from which latter section a flue 26 leads through the casing to a suit-able point of discharge. The section 77 is horizontally mounted in the casing 15 near the lower end thereof and is uipped with a Venturi tube 29 having, desired, the draft regulating attachment shown in Fig. 5 and above described. In this 7 modification the front wall of the casing is provided with doors 44 and 450i like construction and for similar purposes as set forth in the explanation of the other described forms of the heater. Each of the sections from 77 to and including the uppermost section comprising the conduitof this modified form, is provided with a water jacket 82, which water jackets communicate with one another alternately at their rear and front ends as is clearly shown in Fig. 8 of the drawings.

As in the other constructions, each of the sections above the section 77 has at each of its ends an oppositely directed hollow extension 83 which are arranged vertically and at right angles to the body of the section. Thesection 77 or combustion chamber section is rovided at its rear end only with one of t ese extensions which is directed upwardly and co-incides with the extension 83 on the rear lower portion of the secton 78 above and adjacent to the section 77. The hollow extensions at the front end of each pair of such sections above the combustion chamber section, when more than one pair of such sections is employed, is openat its upper portion adjacent the front wall of the casing as is clearly shown in Fig. 10 so as to permit access to the interior of the conduit through the doorways 43 and 46 when the doors 44 and 45 for said ways, respectively, are open. Each of the extensions 83 is provided with an external and horizontally disposed flange 84 to co-ineide with a similarly arranged flange on.the lower portion of the extension 83 of the section located aboveand adjacent to the first named section. These flanges are-connected together by means of bolts extended through suitable openings 85 in said flanges so as to prevent leakage of water or leakage of the products of combustion as they pass through the conduit. The detachable sections above the section 77. are provided at the point of communication between their water jackets as at 84 with suitable means for rendering their connection at said points water tight. Each of the sections of the conduit employed in the present construction of the heater, with the exception of the lowermost one 77, is provided in its longitudinal bore with a series of longitudinally and radially disposed flanges 41 which are spaced from one another and terminate at their inner edges in a circle concentric with the longitudinal axis of the section yet at a distance there- 'from. Mounted on the upper surface of the uppermost section of the conduit and in communication therewith at its rear end is a steam container or chamber 87 which has leading from the upper portion of said chamber or container a discharge pipe 88 for steam generated by the apparatus. This container may be equipped with a blow or safety valve 89 of the ordinary or any preferred construction. The combustion chamber section 77 is provided near its front end and on the lower portion thereof with a water header 90 which has communication through an inlet or water supply pipe 91 with a supply of water, not shown. By the just above described arrangement and construction of the parts of the heater, it is manifest that water supplied through the pipe 91 to the header 90 and from thence to and through the communicating water jackets. of the various sections of the conduit, will flow into the container 87 and-can be maintained with its level as at 92 at a point below the steam outlet pipe 88 and that in its passage through the conduits, steam will be generated and held in the container 87 for discharge through the last named pipe.

While I have shown the heater in its present forms equipped with the combustion chamber or section of the conduit at the lower portion thereof, yet I may invert this construction or arrangement, that is, place the combustion chamber at the upper end of the casing. By so inverting the structure, it is evident that when the device is used in connection with air for the heat absorbing and conveying medium or in case water is used, the air or water can be admitted'to the casing at the lower end or portion thereof and will flow through the conduits therefor without the aid of force or pressure, thus obtaining a counter-current eflect without power, and obtaining the higher eficiencies therefrom.

Modifications illustrating changes in the construction whereby such results may be obtained are illustrated in Figs. 11, 12 and 13. The first mentioned of these figures shows the furnace substantially as illustrated in Fig. 1, wherein means is provided for heating air. In this form of the invention, the fuel is injected into the uppermost section of the combustion conduit, and. the

products of combustion travel downwardly through the various sections taking a tortuous course and passing 011 through the outlet or stack indicated at 26. In this instance, air may be admitted to the casing at the lower opening 17 and may be discharged therefrom at the upper opening 18.

Fig. 12 is a modification of the furnace shown in Fig. 5 of the drawings, and wherein the structure remains substantially the same with the exception that combustion initially takes place in the uppermost of the superimposed combustion chamber sections.

Fig. 13 shows the same idea in connection with a steam heater as disclosed by Fig. 8. In this instance, the fuel is injected into the uppermost of the superimposed combustion chamber sections and passes downwardly as will be obvious. In this instance, steam will be-drawn through pipe 88 from the dome indicated at 100.

Having thus fullly described my invention, what I claim as new and desire to secure by Letters Patent is- 1. A sectional serpentine shaped conduit for the combustion of fuel and for the passage of the products of such combustion provided with co-operating means exteriorly thereon for the radiation or conduction of heat therefrom and co-operating means therein for absorbing heat, the said sections communicatively connected together and spaced from one another, and means embracing said conduit for guiding and directing transversely with respect to and around its sections currents of heat absorbing and conducting fluid medium into intimate contact therewith.

v 2. A serpentine or zig-zag shaped conduit for the combustion of liquid, gaseous or powdered fuel and for the passage of the products of such combustion, having cooperating means exteriorly thereon for the radiation or conduction of heat therefrom, and co-operating means -therein for absorbing heat, said radiating and conduct-ing means being of greater capacity than said absorbing means, the folds or portions of said conduit between its bends being spaced from one another and means embracing said conduit for guiding and directing currents of heat absorbing and conducting gaseone or liquid medium into intimate contact with said conduit.

'3'. A serpentine or zig-zag shaped conduit for the combustion ofliquid, gaseous or powdered fuel and, for the assage of such products of combustion, havmg cooperating.

means exteriorly thereon for the radiation or conduction of heat therefrom, and 00- operating means therein for absorbing heat, said radiating and conductin means being of greater capacity than said aisorbing means,

the folds or portions'of said conduit between its bendsbeing spaced from one. another,

and means embracing said conduit for guidproducts of such combustion, having means being of greaterv capacity than said absorbing means, the folds or portions of said conduit between its bends being spaced from one another, and means embracing said conduit for guiding and directing transversely. with respect to said folds or portions and around the same currents of heatab sorbing and conducting gaseous or liquid medium into intimate contact with said conduit.

5. A serpentine or zi -zag shaped conduit for thecombustion 0 liquid, gaseous or powdered fuel and for the passage of the products of such combustion,- having co-opcrating means exteriorly thereon for the radiation or conduction of heat therefrom,

and co-operating means therein for absorbing heat, said radiating and conducting means being of greater capacity than said absorblng means, the folds or portions of said conduit between its bends being spaced from one another, and means embracing said conduit for guiding and directing transversely with respect to. said folds or portions and. around the same currents of heat absorbing and conducting gaseous or liquid medium into intimate contact with said conduit, so arranged as to have the products of combustion pass in a direction opposite to the course of travel of the heat absorbing medium.

6.. In a heater, the combination with a casing, of a detachably sectional zig-zag or serpentine shaped conduit for the com-- bustion of liquid, gaseous or powdered fuel and for the passage of the products of such teriorly thereon for the radiation or conduction of heat therefrom, and co-operating means therein for absorbing heat, said ra diating and conductin means being of greater capacity than said absorbing means, the detachable sections being communica tively connected together and spaced from one another, and'meansembracing said conduit for guiding and directing currents of a heat absorbing and conductingfgaseous or liquid medium into intimate contact with said conduit, so arranged as to have, the products of combustion travel in a direction opposite to the course assumed by the heat absorbing medium.

7. Ina heater, the combination with an combustionfihaving co-operating means ex- 1 upright casing having an o wing in one" of .its walls near its lower en of a serpentine or zig-zag shaped conduit for the'com bustion of fuel and the-passage of the products ofsuch combustion vertically mounted in the casing and having'an outlet at its up- .per' end through the upper portion of the casing, and an inlet exposed throu b said opening of the casing, means to supp y fluid or powdered fuelinto the inlet end of the conduit, means embracing said conduit for guiding and directing currents of'fluid heat absorbing and conducting medium into intimate contact with said conduit, an inlet for said medium communicating with said guiding means near and'through oneend 0f the casing, and an outlet for said medium leading from said guiding means through and near the other end of the casing.

'- 8. Ina heater, the combination with'an upright casing having an opening inone of its walls near its lower end, of a z'ig-zag shaped conduit for the'combustion of fuel and the passage ofthe productsof combusti'on vertically mounted in the casing and having an outlet at its upper end through the, upper portion of the casing and its other end exposed through said opening of the casing, means to'supply fuel into the inlet end of the conduit, each of the folds of said conduit being provided with a plurality of annular and spaced flanges on its periphery, and at least one of said folds of the conduit being provided internally thereof with a series of longitudinally and radially disposed flanges spaced from one another, an inlet for air under pressure located in the upper portion of the casing and an outlet for air located in the lower portion of the casing.

9. In a heater, a plurality of superimposed conduit sections communicating alternately with the o posite ends of each other and through w ich the products of combustion travel, guide means associated with each section to direct currents of heat absorbing and conducting mediums into intimate contact with the exterior surfaces of said sections, the said guide means being coextensive both'laterally and longitudinally with said superimposed sections, and opositely arranged inlet and outlet openings or said guide means.

GEORGE R LAWRENCE. 

